Aim: How do we use combinations to solve probability problems?
At the end of the lesson, you will be able to...
define a combination
discover a formula for the combination of n different things taken r at a time
identify the notations used with combinations
explain the circumstances under which a permutation should be used or under which a combination should be used
apply the combination formula
apply the counting principle along with combinations to count the elements in the sample space
use a calculator to compute combinations
use calculators to solve probability problems
Copy these questions down into your notebook. Answer them as you watch the video.
What is a combination? Does order matter?
How is a combination differ from a permutation?
How do you know when to use a permutation or a combination when solving a problem?
What are the three ways to write a combination? Which way should you write to enter the data into a graphing calculator?
How can you use the graphing calculator to find a combination?
Video
Video
Classwork: solve the following problems:
1. How many different combinations of five letters can be selected from the alphabet? (Ans: 26C5 = 65780)
2. How many different combinations of 5 letters can be drawn from the alphabet if 3 are consonants and 2 are vowels? (21C3 x 5C2 = 13300)
Journal entry: The lock on your locker is probably called a combination lock. It needs a sequence of numbers rather than a key to open it. Is the word "combination" an appropriate description of would "permutation" lock be a more mathematically correct name? Explain
At the end of the lesson, you will be able to...
Copy these questions down into your notebook. Answer them as you watch the video.
Video
Video
Classwork: solve the following problems:
1. How many different combinations of five letters can be selected from the alphabet? (Ans: 26C5 = 65780)
2. How many different combinations of 5 letters can be drawn from the alphabet if 3 are consonants and 2 are vowels? (21C3 x 5C2 = 13300)
Homework: #3- 57 odd
Perm_and_Com_1.JPG
Perm_and_Com_2.JPG
Answers:
A-Perm_and_com.JPG
Journal entry: The lock on your locker is probably called a combination lock. It needs a sequence of numbers rather than a key to open it. Is the word "combination" an appropriate description of would "permutation" lock be a more mathematically correct name? Explain